Noun obstructer has 2 senses

• obstructer(n = noun.person) obstructionist, obstructor, resister, thwarter - someone who systematically obstructs some action that others want to take; Array
is a kind of controversialist, disputant, eristic
has particulars: naysayer, stonewaller
Derived form verb obstruct₁

• obstructer(n = noun.artifact) impediment, impedimenta, obstruction, obstructor - any structure that makes progress difficult; Array
has particulars: bar, barrier, blockade, block, blockage, closure, occlusion, stop, stoppage, encumbrance, hinderance, hindrance, hitch, incumbrance, interference, preventative, preventive, obstacle, tumbler
is a kind of construction, structure
Derived form verb obstruct₂